Earlier this week, Schlessinger announced she was ending her successful radio show a week after she went on a five-minute rant in which she used the N-word 11 times.

Play

Jennifer Aniston Blasted for Using R-Word

Now Aniston is the latest celebrity to come under fire for using the word "retard," which is considered offensive, during an interview Thursday on "Live With Regis and Kelly."

While discussing dressing up as Barbra Streisand for Harper's Bazaar, Aniston let the word slip.

"You're playing dress up!" Regis Philbin told her.

"Yes, I play dress up!" she replied. "I do it for a living, like a retard!"

The reaction was immediate and harsh.

"Special Olympics is always disappointed when the R-word is used, especially by someone who is influential to society," the group's spokeswoman Kirsten Seckler told ABCNews.com. "The pervasive use of the R-word, even in an off-the-cuff self-deprecating manner, dehumanizes people with intellectual disabilities and perpetuates painful stereotypes that are a great source of suffering and negative stigma."

Play

Dr. Laura Schlessinger Apologizes for N-Word Rant

Aniston, who took Bill O'Reilly to task on "Good Morning America" for saying she was "destructive to our society" after she defended single motherhood, has so far stayed mum about the flap. Her rep did not respond immediately to ABCNews.com's request for comment.

Given the controversy generated by both Schlessinger and Aniston, here's a look at five words that some advocacy groups would like to see put to bed already.

The N-Word

In 2007, the NAACP held a public funeral for the N-word, complete with coffin and headstone, during its annual convention in Detroit.

Play

null

"Today we're not just burying the N-word. We're taking it out of our spirit," then Detroit Mayor Kwame Kilpatrick said at the time. "Die N-word, and we don't want to see you 'round here no more."

If only it were that simple. But every year, it seems, some public figure is heard using the N-word, reigniting the firestorm over its use. Earlier this summer, it was Mel Gibson during an argument with his ex-girlfriend Oksana Griegorieva, in which he told her: "If you get raped by a pack of n***ers, it will be your fault."

Now Schlessinger is in the hot seat, although she has her defenders, including Sarah Palin.

"Does anyone seriously believe that Dr. Laura Schlessinger is a racist?" the former Republican vice-presidential candidate asked in a post on her Facebook page.

"Those who oppose her seized upon her mistake in using the word (though she didn't call anyone the derogatory term) to paint her as something that she's not," wrote Palin, adding that she too has felt "shackled" by critics and sympathizes with Schlessinger.

Schlessinger, who apologized for using the word, has said she did so to make the point that black comedians use it freely. But even conservative black scholar John McWhorter said that's unacceptable.

"As Jews may observe kosher laws, so too, America can observe a historically minded brand of politesse under which whites step away from a term that blacks use in a different meaning," he wrote on the website the Root.

The R-Word

While defending Schlessinger, Palin attacked White House Chief of Staff Rahm Emanuel -- whose name she misspelled -- for using the so-called R-word earlier this year.

"Curiously, the same criers over this issue didn't utter a word when White House Chief of Staff Rahm Emmanuel [sic] called a group protesting the Obama Administration's actions, 'f——— retards,'" wrote Palin, who has a son with Down's syndrome.

Emanuel apologized to the Special Olympics after the Wall Street Journal reported his remark. President Obama also found himself apologizing after he compared his bowling skills to the Special Olympics.

Since last year, the Special Olympics has been campaigning to end the use of the word. "We're really not out to ban anything," spokeswoman Seckler said. "What we want to do is get people aware of the use of this word and how it hurts people with intellectual disabilities."

So far, 145,000 people nationwide have taken a pledge on the Special Olympics' website www.r-word.org to not use the word.

The F-Word

No, not the one most people think of, but the word "faggot" or "fag," which is derogatory to gays. But that's not the only one.

"We have some words we'd like to ban, particularly among members not in the LGBT community, such as 'fag/faggot,' 'tranny' and 'he-she,'" David Hauslaib, editorial director of Queerty.com told ABCNews.com.

Like the N-word, these words are often used by the people most offended by them, but Hauslaib said that doesn't give others a free pass to use them.

"There's a reasonable argument that anyone using these words is doing harm, but it's unrealistic to think members of the LGBT community will stop saying "fag" in jest, and that's an individual's right," Hauslaib said. "Words that are derogatory to any community generally get a pass when used by those who belong; anyone outside that culture, however, doesn't have permission because they are not directly impacted by such language."

Wetback

This term, once used by the U.S. government in 1954 when it launched Operation Wetback to deport a large number of Mexicans, has become a slur against other Hispanics, especially illegal immigrants.

Once again, Mel Gibson proved an equal opportunity offender when he used the term in an argument with his ex.

In a tape recording that was released this summer, Gibson was reportedly heard threatening to turn their daughter's nanny in to immigration authorities, "I will report her to the f**king people that take f**king money from the wetbacks."

There's been plenty of pushback against usage of the word, especially from Mexican-Americans. In Texas, they were able to marshall forces in 2009 to have radio personality Don Pryor removed from the air after he repeatedly used the term.

Towelhead

Like raghead, towelhead has been used as an ethnic slur against Arabs, Indians and others who wear traditional headdresses, such as turbans or keffiyehs.

Since 9/11, though, the usage has become more widespread to denigrate anyone from an Islamic nation. Muslims are fighting back against use of the word.

When director Alan Ball called his 2008 movie "Towelhead," the Greater Los Angeles Area office of the Council on American-Islamic Relationscalled on Warner Bros. to change the title.

In the letter to Warner Bros. Chairman and CEO Barry M. Meyer, CAIR-LA Executive Director Hussam Ayloush said: "It is unfortunate that a major film studio would choose to exploit an ethnic slur as a sensational promotion for a movie. Mainstreaming a bigoted term in this manner will only serve to legitimize and normalize anti-Muslim prejudice in our society."